A spreader for powdered particulate material including filter media mounted on a vehicle such that it serves a dual purpose of collecting particulate material through a vent opening when a vessel is being loaded and collecting dust adjacent an outlet opening when the powder is being dispensed.
Using soil stabilization techniques, problem soil can be turned into a solid working surface, such as a lime stabilized road, in just a matter of hours by applying an additive which is right for specific needs and environmental considerations. Soil stabilization techniques are used for repairing road surfaces, airports, parking lots and runways and for numerous private industries.
Soil stabilization is accomplished by introducing materials such as lime, fly ash, cement or bentonite into the problem soil. Undercutting and/or backfilling the subgrade can be very time consuming and expensive. Stabilization can turn the subgrade into a working platform in a fraction of the time at reduced expense.
When soil stabilization techniques are used, projects are not delayed by wet conditions. Soil is dried and a working platform is created. Pumpy soils are bridged allowing you to pass proof roll tests. Lower maintenance costs of finished product. Increased soil strength which increases structural value of pavement and often decreases the amount of aggregate base needed. And the best part is less down time for the project, significant cost savings and ultimately higher profit. Depending on the additive which is right for specific needs and environmental considerations, the additive is loaded in a spreader and distributed to the working area in the method required. Materials must then be properly mixed with the soil at the given spread rate by dry or slurry methods with the appropriate addition of water.
The subgrade and additive are then compacted in preparation for shaping and grading. The soil is now workable for shaping and grading.
Using other conventional methods, this stage could take days or even weeks in the event of inclement weather. The final step in the stabilization is sealing of the stabilized soil in order to prevent the possibility of penetration by rain. An oil cure is necessary for soil cement. The results are obvious.
Lime, fly ash, cement, bentonite and other additives used for stabilization of problem soil, are often powder which forms a cloud of dust when it is spread. Lime, some times called quicklime, is any of various forms of calcium oxide differing chiefly in water content and percentage of constituents such as silica, alumina, and iron. Fly ash is a fine particulate ash sent up by the combustion of a solid fuel, such as coal, and recovered as a byproduct for various commercial uses. Fly ash is very light and powdery. Bentonite is an absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.
U.S. Pat. No. 4,990,025 discloses a method and apparatus for simultaneously tilling a sufficiently deep layer of soil along a roadway or improvement site to provide a stabilized and/or sealed soil base, mixing in a sufficient amount of fly ash or other suitable binder, filler, or sealer material and also mixing in a sufficient amount of water in the form of a spray to provide a durable, reliable, stabilized and/or sealed soil base. A water manifold is mounted on the outside of a hood covering a rotary tiller which tills a thick layer of soil. A plurality of tubes extend from the water manifold through the shroud to a region above the rotary tiller, injecting a dense, uniform spray of water inside the housing, prewetting the soil base being tilled. Water is supplied by a tanker truck moving slowly alongside a tractor on which the tiller is mounted. A second manifold is mounted behind the water manifold and includes a plurality of nozzles extending through the shroud. A flexible hose conducts powdery filler or binder material from another tanker truck moving alongside the filler/stabilizer machine. The powdery filler/binder material is uniformly mixed with the prewetted soil being tilled. The dense spray of water both prewets the soil being tilled and prevents powder filler, binder, or sealer material from spreading outside the hood and causing dust/particulate pollution.
U.S. Pat. No. 4,032,074 discloses a fertilizer spreader with a curved shroud to control material being spread.
U.S. Pat. No. 4,061,221 discloses a dust controlling loading chute apparatus for particulate material. The apparatus includes a flared hood having a flexible lower skirt connected to a support ring. Dust particles swirling under the hood and skirt are drawn up through the annular space between the inner and outer pipes to a collector.
U.S. Pat. No. 4,757,918 discloses a vehicle mounted spreader.
U.S. Pat. No. 4, 969,494 discloses a filtering device for filtering a moving gaseous atmosphere in an installation for unloading pulverulent product. A supply sleeve is connected between the base of a silo and the circular filing orifice of a mobile container.
U.S. Pat. No. 5,518,343 discloses a dust-free powder substance delivery and filter system for use in delivering powder material. Powder entrained in an air stream is separated from the air and filtered air is exhausted.
U.S. Pat. No. 6,065,922 discloses a powder loading device with dust containment system which includes a cover for a powder loading device which prevents the escape of loose powder when the powder is transferred from a storage container to a receiving container.
A long felt need exists for a spreader vehicle equipped with apparatus including filter media mounted on a vehicle such that it serves a dual purpose of collecting particulate material through a vent opening when a vessel is being loaded and collecting dust adjacent an outlet opening when the powder is being dispensed.
A spreader truck for spreading particulate material, such as lime, fly ash, cement or bentonite onto a subgrade, roadway or other surface, has a vessel for storage of a volume of powdered material and has a discharge opening. A dispenser, mounted adjacent the discharge opening, has an elongated hopper configured for discharging powdered or particulate material over substantially its entire length onto the subgrade, roadway or other surface. A dust collector, mounted above a hopper on the truck, contains a filter media, and a blower is mounted for drawing air through the filter media.
The vessel on the truck has a vent opening and the dust collector has a vent hose communicating with the vent opening, such that the blower draws dust and contaminated air from the vessel through the filter media.
A dust collector hood is mounted for receiving dust formed when powdered material is discharged from the dispenser. The dust collector hood is connected through one or more tubes communicating with the inside of the dust collector hood and the dust collector, the blower being mounted for drawing air from the dust collector hood through the filter media.
The spreader truck is preferable equipped with a source of pressurized air connected through a valve to one or more blow pipes, having at least one opening positioned for delivering air through the filter media for removing dust from the filter media which falls down into the hopper below the filter media.